Benitoiteis a rare blue barium titanium silicate mineral, found in hydrothermally altered serpentinite. Beniotite is a very rare mineral that was discovered in 1907 in San Benito County inCalifornia.
It was originally mistaken for sapphire. Benitoite fluoresces under short wave ultraviolet light, appearing bright blue to bluish white in color. The more rarely seen clear to white benitoite crystals fluoresce red under long-wave UV light.
Benitoite occurs in a number of sites, butgemstone qualitymaterial hasonly been foundin California. In 1985 benitoite was named as theofficial state gemof California.
Benitoite has the rarest form of crystal structure in the world. It belongs to the Hexagonal System, it’s Class is Ditrigonal -Dipyramidal. It’s light dispersion or internal fire is greater than that of diamond. Dispersion is the splitting up of white light into its individual wavelengths, what we see as colors. A benitoite that has good clarity, color and cut will showgreater firethan a diamond.
The blue Benitoite on a white Natrolite matrix and usual association with black Neptunite makes a very aesthetic mineral specimen. Benitoite has a rare 5 pointed crystal form, and an even rarer 6 pointed form, “star of David”, with about 24 samples known.
Benitoite isassociated withother rare minerals such as black-red neptunite, snow white natrolite and brown-yellow joaquinite. Since the only source of this rare combination occurs at San Benito County, California
With the color of the most valuable tanzanite, it is easy to see why it is so valued. Gem quality Benitoite can be worthmore than Diamonds, Sapphire, Ruby,EmeraldorTanzanite. A clean, rare 1 carat cut benitoite sells between$6500and$8000, depєɴԀing on color, cut and clarity.
The cost increases greatly as the size of the cut stone increases due to the rarity of large facet grade crystals. Current market pricing of clean, good color, and well cut faceted benitoite over 2 carats, is $10,000 per carat. Even uncut, ɾօυɢҺ stones and good mineral samples in matrix can run in the thousands.
It is one of the only gemstones that is naturally deep blue incolor, not needing heat or any other treatment to achieve it’s color. It can be found in differing shades of blue, violet, white, clear, and on very rare occasions very pale pink, but the Deep Blue color is the most desirable. Science still cannot identify exactly what gives benitoite it’s amazing color, and scientists have been unable to duplicate or replicate benitoite’s crystal growth or fluorescent nature.
Properties of Benitoite
Chemical formula:BaTiSi₃O₉
Coloris typically blue, but also colorless and yellowish.
Lusteris vitreous.
Transparency: Crystals are transparent to translucent.
Crystal Systemis hexagonal; bar 6 m 2
Crystal Habitsinclude the flattened six faced dipyramid that has a distinct triangle shape often modified by minor faces. Also found as small grains.
Cleavageis absent.
Fractureis irregular.
Hardnessis 6 – 6.5
Specific Gravityis approximately 3.6 (above average)
Streakis white.
Other Characteristics:Nearly all specimens fluoresce blue under UV light.
Associated Minerals include serpentine, neptunite, natrolite, joaquinite, sanbornite, taramellite, albite and fresnoite.
Notable Occurrencesinclude only the mines of San Benito County, California, USA for good excellent crystals. SW Texas produces tiny grains in eocene sands as well as some other California localities.
Best Field Indicatorsare crystal habit, fluorescence, color, associations and locality.
Where to Find Benitoite in California
Although commercial mining is no longer being conducted at the mine, People could now dig thru theold mine dumps, tailings and virgin ground to try and find their own treasured jewels. The Fee dig is presently only open on the weekєɴԀs and will require a phone reservation. All reservations require a phone call for confirmation.
Pricing:
– $70 per person
– Kids 12 and younger, only $20
– Seniors 70 and over with proof of current Rockhound Membership from any Federation Club is half price, $35
Reservations must be made via aphone call: (559)-287-4096
Address:48242 Los Gatos Creek Rd, Coalinga, CA 93210
